1. Field of the Invention
This invention relates generally to compositions and methods for improving joint health in animals and particularly to the use of sulfur containing amino acids and manganese to decreasing cartilage abnormalities in animals.
2. Description of the Prior Art
Virtually all joints have cartilage. Cartilage is important in the body of animals for providing flexibility, compressibility under pressure, cushion, tensile strength, range of motion and smoothness of movement within joints. Examples of joints having cartilage include fingers and toes, neck, knee, hip, shoulder and the like. Animals can suffer from a number of conditions where cartilage is negatively affected thereby bringing about a reduction in the joint's flexibility, compressibility and often times resulting in a generalized inflammation of the joint and/or tissue surrounding the joints. Such animal then has significant loss of joint function and experiences pain.
U.S. Pat. No. 5,587,363 to Henderson proposes a composition for protection, treatment and repair of connective tissues in humans and animals and a method for the treatment of connective tissues in humans and animals by the administration of the composition. The composition includes amino sugars and glycosaminoglycans. U.S. Pat. No. 6,255,295 to Henderson proposes a composition for protection, treatment and repair and reducing the inflammation of connective tissues in mammals and the method for protection treatment and repair of connective tissues in mammals by the administration of the composition. The composition includes at least two compounds selected from s-adenosylmethionine, an amino sugar, and glycosoaminoglycan-like compound. The composition optionally includes manganese and the composition also optionally includes methyl donors and methyl donor cofactors. U.S. Pat. No. 6,271,213 to Henderson proposes a composition for protection, treatment and repair and reducing the inflammation of connective tissues in mammals and the method for protection treatment and repair of connective tissues in mammals by the administration of the composition. The composition includes at least two compounds selected from s-adenosylmethionine, an amino sugar, and glycosoaminoglycan-like compound. The composition optionally includes manganese and the composition also optionally includes methyl donors and methyl donor cofactors. U.S. Pat. No. 5,952,367 to Pak proposes a method of treating pain caused by tendonitis, arthritis and the like comprises administering the effective amount of a non-steroidal anti-inflammatory drug and ingesting an amount of methionine and a sugar in combination.
Kroger et al. (1999) the Effect of Tryptophan plus Methionine-5-Azazytidine and Methotrexate on Adjuvant Arthritis of Rat; Gen. Pharm. 33:195-201 report a treatment with combination of tryptophan and methionine alone stimulate arthritic reactions. However, treatment with the two drugs 5-azazytidine and methotrexate in combination with tryptophan and methionine clearly reduced development of the adjuvant arthritis and this effect is stronger than either the 5-azazytidine or methotrexate alone. Agency for Health Care Research and Quality (2002) Evidence Report Technology Assessment No. 64 report that studies were identified in the literature that included a meta analysis of the efficiency of S-adenosyl-L methionine (SAMe) to decrease the pain of osteoarthritis. Results show that when compared with non-steroidal anti-inflammatory medication, treatment with SAMe was not associated with statistically significant difference in outcomes. However, one randomized clinical trial showed an effective size in favor of SAMe of 0.20 compared to a placebo, thus, indicating a decrease in the pain of osteoarthritis. Johnston (1997), Orthoarthritis. Veterinary Clinics of North America; Small Animal Practice 27:699-720 reports that osteoarthritis is a slow progressive disorder of synovial joints that affects about 20% of the canine population over one year of age. This joint disorder is characterized by the loss of balance between synthesis and degradation of articular cartilage constituents leading to subsequent erosion of joint cartilage, remodeling of underlying bone, osteophyte formation and variable degrees of synovitis. Martinez et al. (1997) Acquired conditions that lead to osteoarthritis in a dog. Veterinary Clinics of North America: Small Animal Practice; 27:759-775 report that some of the most common causes of secondary osteoarthritis seen in companion animals are anterior cruciate ligament rupture, osteochrondritis dissecans, fragmented coronoid process and hip dysplasia. Other examples of cartilage affected conditions include but are not limited to osteochondrosis, synovitis, bacteria purulent arthritis, osteoarthropathia psoriatica, subchondrial cystic lesions, physitis, angular limb deformities and cuboidal bone malformation.
Most large dogs develop arthritis as they age. Large dog breeds are more susceptible to arthritis due to their increased mass and/or genetic disposition. Large dogs are not the only animals at risk of arthritis and other cartilage conditions. Hardie et al. (2002) Radiographic evidence of degenerative joint disease in geriatric cats. JAVMA 220(5):628-632 report that arthritis and other degenerative joint diseases have been commonly recognized in dogs and such conditions have been shown to be prevalent in cats. Other animals at risk of developing cartilage affecting conditions include, but are not limited to, mammals such as canine, feline, equine, hicrine, ovine, porcine, bovine, human and non-human primate species, and birds including turkeys and chickens.
Known methods for decreasing cartilage abnormalities in an animal have limited efficacy. There is, therefore, a need for new methods and compositions for treating, preventing, or improving such conditions in animals.